The field of the invention relates generally to an integrated gasification combined cycle (IGCC) system, and more particularly, to an IGCC system that includes an adiabatic axial air compressor.
In at least some known IGCC power plants, hydrocarbonaceous feeds, including low value feeds, are reacted with high purity oxygen, such as approximately 95% oxygen purity, to produce combustion products, including syngas, at a temperature of about 2200° F. to about 2700° F. The resulting syngas is combusted within a combustion turbine to produce electric power.
Moreover, in at least some known IGCC power plants, the oxygen is supplied by an air separation unit (ASU). More specifically, to supply the oxygen from the ASU, air supplied to the ASU is initially compressed using an intercooled air compressor. However, within known intercooled air compressors, thermal energy from each stage of cooling is transferred to cooling water rather than being used within the power plant. Such thermal energy is transferred rather than used within the plant because the thermal energy within the intercooled air compressor is generally below about 200° F. Moreover, the transfer of the thermal energy to the cooling tower requires additional power consumption by the cooling water circuit. Accordingly, a need exists for an IGCC power plant with improved heat efficiency. The embodiments described herein seek to improve the heat efficiency of an IGCC power plant.